Steam-generator.



no. 696,!65'. Patented Mar. 25, I902. n. .1. EARNSHAW. I

stem GENERATOR.

(Application filed my 18, 1901.) (No Model.)

UNITED STATES PATENT OFFICE;

IIENRY P. J. EARNSHA\V, OF HYDEPARK, MASSACHUSETTS.

STEAM-G EN ERATO R.

SPECIFICATION forming part of Letters latent No. 696,165, dated March 25, 1902.

Application filed May 16, 1901. Serial No. 60,443. (No model.)

To all whom, it may concern:

Be it known that I, HENRY. P. J. EARNSHAW, a citizen of theUnited States,residing at Hydepark, in the county of Norfolk and State of Massachusetts, have invented an Improvement in Steam-Generators, of which the following description, in connection with the accompanying drawings, is a specification, like numerals on the drawings representing like parts.

This invention relates to steam-generating devices such as are applicable to any ordinary horizontal boiler; and it comprises the usual circulating-pipes arranged underneath the boiler and connected at their front end with a water-box, which water-box is in turn connected by the usual discharge-pipes with the front end of the boiler, preferably above the water-line. The rear ends of the circulating-pipes are rigidly secured to one or more headers, which are connected to the muddrum by a slip-joint orexpansion-joint. The mud-drum is connected to the under side of the boiler by a connection having what I have termed a circulating-head, said head being lpreferablyhoodshaped and extended into the boiler, but having its mouth extending below the bottom of the boiler. The connection between the boiler and the mud-drum extends into the mud-drum, and the header or headers are connected to the top of the mud-drum, so that as the water circulates through the circulating-pipes it is drawn from the bottom of the boiler into the mud-drum and then in turn taken from the mud-drum through the headers to the circulating-pipes. By connecting the mud-drum to the boiler by means of my circulating-head I prevent any sedinnent from collecting on the bottom of the boiler, for the rapid circulation of the water will take with it the sediment through the connection and into the mud-drum, the sediment remaining at the bottom of the muddrum, while the clear water passes to the top thereof and out through the headers to the circulating-pipes, as above described. Since the bottom of the mouth of the circulating- -head is below the bottom of the boiler, there is no chance for any sediment to accumulate 011 the bottom of the boiler. By making the slip or expansion joint between the headers and the mud-drum it will be seen that the boiler will be subjected to no strain whatever, for the expansion of the circulatingtubes will simply move the headers relative to the mud-drum, the slip-joint between the headers and the mud-drum allowing this.

The mud-drum, therefore, and the boiler are relieved'from all strain due to such expanr' sion.

Another feature of the improvement consists in setting the mud-drum into a pier or support made of fire-brick or similar material, so that the lower portion of the muddrum, or that in which the mud and dirt accumulate, is protected from the action of the flames, and thus prevents the mud from be coming eaked by heat.

Another feature of my invention is-in connecting the discharge-pipe from the WaterboX to both the end and central portion of the box, so as to prevent any dead-water remaining in the box and establish a'free circulation through the box.

Still another feature-of the invention resides in the particular manner -in which the circulating-pipes are connected tothe headers whereby the pipes are protected ,from in- In the drawings, Figure l is a:p erspective viewof my improved steam-generating de-.

vice, the boiler to which it is attached being shown in dotted lines. I Fig. 2 is a section of the mud-drum. Fig. 3 is asection of the circulating-head. Fig. lis a vertical section of the front water-box. Fig. 5 is a detail showing the slip-joint between the mud-drum and the headers, and Fig. 6 is a detail showing the manner of connecting the circulatingpipes to the headers.

The steam-generator comprises a boiler 3 of any ordinary horizontal type (shown indotted lines) and the usual circulating-pipes 4, which are connected at their front ends to a water-box 5 and at their rear ends to headers 6 and 7, which in turn are connected to the boiler, as will be hereinafter described. The water-box 5 has extending upwardly therefrom the usual discharge-pipes 8,which enter the boiler at the front end thereof and preferably above the water-line. The parts thus far described are more or less common in steam-generators, and their function, therefo re,will not need to be specifically described.

to the circulating-pipes.

Heretofore, so far as I am aware, it has been the common practice to attach the header rigidly to the boiler and to provide a slip or expansion joint between the circulating-pipes and the header to allow for the expansion of said pipes; but in such construction the connection between the header and boiler must be of sufficient strength to withstand the pressure in a horizontal direction on the header due to the boiler-pressure,which may amount to several tons, and it is one of the objects of myinvention to obviate the necessity for such a heavy connection between the header and boiler. In order to accomplish this, I preferably connect the mud-drum 10, which is supported upon a suitable pier or support 11, as hereinafter described, directlyto the boiler and connect the headers to the mud drum by means of a slip or expansion joint, the headers in turn being rigidly connected Referring to Figs. 2 and 3, it will be seen that the upper end of the mud-drum is provided with the flanged neck 12, which is bolted to the flanged collar 13, said collar in turn being fastened to the under side of the boiler-shell in any suitable way. The opposite sides of the mud-drum have connected thereto at their upper ends the T connection 14, the ends of said connection being of a size to slidingly fit nipples 15 on the front and rear headers 6 and '7, respectively. To make a tight joint, I screw upon the nipples the collars 17, having the recesses to receive a s itable packing 18, said collars and packing forming, in effect, a stuifing-box.

The circulating-pipes 4 are rigidly secured at their rear ends to the headers 6 and 7, respectively, as will be hereinafter described, so that as the said pipes expand and lengthen the headers move therewith; but owing to the slip-joint between the headers and the T 14 the headers may have afree movement without subjecting the mud-drum or the boiler to any strain. Moreover, since the headers have a slip-joint connection with the boiler and are rigidly secured to the circulating-pipes and said pipes in turn secured to the water-box, it will be seen that any pressure on the headers due to boiler-pressure is borne entirely by the headers themselves and the circulating-pipes, and the boiler is not subjected to any strain from this cause. The connection between the headers and boiler may be comparatively light, therefore, thus reducing the cost of the generator.

Another feature of my invention resides in taking the water from the boiler into the mud-drum and then from the mud-drum to the headers and the circulating-pipes, and, as shown in Fig. 2, the neck 12 of the muddrum has attached thereto and extending into the mud-drum the pipe or conduit 19, so

the water will remain at the bottom of the mud drum and accumulate therein, from whence it may be blown off through the blowoif pipe 20. (Shown in dotted lines, Fig. 1.)

To protect the lower portion of the muddruin from the heat of the furnace, I preferably set the same in a suitable recess in the pier 11, as shown in Fig. 1, the drum having, preferably, an annular flange 21, which rests upon the pier to support said mud-drum.

In one familiar form of so-called back connection between the boiler and the headers said back connection is attached to the boiler at the rear end thereof. The disadvantage of this form is that the openinginto the boiler must necessarily be slightly above the lowest portion of the boiler, and consequently as the water circulates through the circulatingpipes a layer of sediment will accumulate on the bottom of the boiler, which if left to remain will soon'cause the boilerto deteriorate. In order to remedy this disadvantage, the back connection has sometimes been connected to the bottom of the boiler. While this construction permits to some extent the accumulation of sediment, yet it has been found that during the circulation of the water it was drawn vertically from the boiler through the back connection and no current was established along the bottom of the boiler. With this construction, therefore, sediment would settle on the boiler-bottom to such an extent as to injure the same. I obviate this difficulty by using in connect-ion with my back connection a hood-like circulating-head which establishes a current along the boilerbottom, which keeps the boiler perfectly clean.

Referring to Fig. 3, it will be seen that the collar 13 is recessed in its lower flange, and said recess receives the flange 23 of a spider 24, the flange 23 of the spider being clamped between the flanges-on the neck of the muddrum and the collar 13, as shown. To the upper end of the spider 21 is attached the hood-like circulating-head 25, the said head having its mouth directed toward the front of the boiler and having the lower portion of.

the mouth, as at 26, slightly below the bottom of the boiler. With this construction as the water in the circulating-pipes is heated and the steam is generated a circulation commences through the pipes and colder water is drawn through the back connection into the mud-drum and out through the headers, as will be obvious. Since the mouth of the hood-like circulating-head opens toward the front of the boiler and has the portion 26 below the bottom of the boiler, it will be seen that as the water commences to circulate it will be drawn into the mouth of said circulating-head from along the bottom of the boiler, thus establishing a current along the boilerbottom, which current will carry with it any sediment that may be on the boiler-bottom and deposit the same in the mud-drum. I am thus enabled to keep the boiler-bottom perfectly clean, and =thus-prevent any scale forming thereon. By-making the spider, as

shown, withthe uprights 24 spaced from the inner wall of the collar, the water will circu-- late around the same'and the intense heat will not injure the circulating-head in any way.

To increase the capacity of the steam-generator, I have increased the usual number of circulating-pipes 4, and, as illustrated in Fig. 1, there are two seriesof pipes, one series comprising the group of four central pipes, which: are connected at their rear end to the front. header 6, and the other series comprising the Y other four pipes, there being a group of two such pipes at either side of the central series, and said second series of pipes are connected to the outside end of the rear header, as plainly seen. It will beobvious-of course that the number ofpipes may-be greater than those illustrated, if-desired; but-by using the front and rear headers I am enabled to employ the'center series of pipes which has heretofore been impossible with the old construction. The front end ofthe circulating-pipes enter the water-box 5, as usual, and the water inthe water-box 5 .is-discharged-through the discharge-pipes into the boiler. Inorder to prevent any dead-water accumulating in the center of the water-box," I provide each discharge-pipe 8 with a branch connection 28,

communicating'with the centerof the box, so

that the water in the box 5'has a free circulation. said box5in the three compartments,as shown invthe sectional view-Fig.4, the outer compartment 30 receiving waterfromthe outside pipes, connected to the rear head 7, and said:

water passing directly tothe discharge-pipes 8, and the central compartment 31' receiving water-from the central-seriesofcirculatingpipes, connected to the front header 6 and delivering water through the branch connection 28. This construction I find of great advan-v tage, because it permits free circulation ofthe water through the water-boxo. I will preferably construct my water-boxwith the.bot-.

tom thereof bulging or slightly rounding, (see Fig. 1,) so that the-same may accomodate itself to the arch-support'on which it rests, even though the boiler is not exactly horizontal. As stated above,'the circulating-pipes t are. rigidly connected to the front and the rear.

headers, respectively, and I have devised a special form of OOHDGGDIOILWhlOh has the function of protecting the threads on the pipe from being burned or destroyedrby the intense heat from thecombustion-chamber or from beco'mirigso clogged or filled with dirt,

ashes, &c., as torender it impossible to re-. move the nuts when it is desired to removeor replace any of the circulating-pipes.

Referringto Fig. 6,36 represents .nipples on the headers, to which the pipes 4 are to beiconf 37 represents a collar or nut screwednected. upon the nipples 36 andinto which the-pipes t are screwed, thus rigidly connecting the said filed August 2, 1901', which is a Preferably I will also partition the.

Patent, is-

pipes to the nipples. The collar or nut 37 is providedwith the recess to receive a packingring 38, and a lock-nut'39 is screwed onto the pipe 4:, said lock-nutbeing provided with a corre-- sponding recess, which, in connection with the recess in-the nut 7, receives the packingring 38, thus makinga tight joint. The outer end of the nut 39 has an annular recess around the pipe 4, formed by the projecting flange 40, and in said recess is placed a protecting-packing 41 of suitable material, such as asbestos, said packing covering the exposed threads on the pipe 4 and preventing them from being destroyed'by the intense heat or from getting clogged 'with dirt, ashes, the. It sometimes happens thatit isfvery desirable to remove one or more of. the circulating-pipes-for some reason, andwith my improved construction this can always bedon'e by-simply removing the packing 41,-for the threads are preserved and the nuts are prevented from getting rusted on, .while inthe ordinary construction it is frequently impossible to disconnect the pipes from the headers after the d'evice'has been in use a short time. I r

The above construction for protecting-the exposed threads on a-circulating-pipe forms no part of my present invention, however, J

and the boiler, said connections including aslip or expansion joint. t

2. A steam-generating device'adaptedto be connected to a horizontal boiler, said-device including a mud-drum-adapted to be connected-to the under side of said boi'ler,'-a-*header connected-to the mud-drum by an expansion joint, and circulating-pipes rigidly connected to said header.

3; A steam-generating device adapted to be connected toa horizontal boiler, said device including a mud-drum adapted to beconnected to theunderside of the boiler, front and rear headers either-side of said mud-drum,

:flexible connections between said headers andthe top *ofthe mud-drum, and circulating-pipes communicating with the'headers.

t. A steam-generating device adapted to be connected-to ahorizontal boiler, said'device' including a mud-drum, a connection between the bottom ofthe boiler and the mud-drum,

and a plurality of circulating-pipes connected 'tothemud-drumand extending-beneath the boiler whereby. the water, as it circulates, is taken from thelboiler and through the muddruminto the circulating-pipe.

'lto

&

5. A steam-generating device adapted to be connected to a horizontal boiler, said device including a mud-drum, a connection between the bottom of the boiler and the mud-drum, said connection including a pipe extending into the mud-drum, and a plurality of circulating-pipes connected to the top of the muddrnm whereby, as the water circulates it is drawn through the mud-drum and delivered to the circulating-pipes.

6. In a steam-generator, a boiler, a plurality of circulating-pipes below the boiler and connected thereto at the rear end thereof, said circulating pipes being divided into three groups, a water-box having a central compartment and separate end compartments, one group of said pipes connecting with each compartment, and discharge-pipes connecting each end compartment of the water-box to the front end of the boiler, each of said pipes having a connection with the central compartment.

7. In a steam-generator, a boiler, a plurality of circulating-pipes below the boiler and connected thereto at the rear end thereof, a water-box at the front of the boiler and connected to the circulating-pipes, a dischargepipe at either end of the water-box connecting the same with the boiler, each of said dischargepipes having a branch connecting with the central portion of the water-box.

8. In a steam-generator, a boiler, circulating-pipes, and a back connection between said pipes and boiler, said back connection being connected to the under side of the boiler and including a hood-like circulationhead extending into the boiler, and situated below the normal water-line.

9. In a steam-generator, a boiler, circulating-pipes, and a back connection between said pipes and boiler, said back connection being connected to the under side of the boiler and including a hood-like circulationhead extending into the boiler, the mouth of said circulation-head having a portion thereof below the bottom of the boiler.

10. A steam-generating device adapted to be connected to a horizontal boiler comprising a plurality of circulating-pipes, a back connection adapted to connect the same to the boiler, said back connection including a collar to be secured to the under side of the boiler, a hood-like circulating-head secured to said collar and extending into the boiler with its mouth toward the front of the boiler,

the lower portion of said mouth being below the bottom of the boiler whereby the circulation of the water through the back connection carries all the sediment from the boiler.

11. A steam-generating device for a horizontal boiler, said device comprising a plurality of circulating-pipes, a header to which said pipes are rigidly connected at one end, a water-box rigidly connected to the other end of said pipes, said water-box, circulatingpipes and header forming a rigid construction, and a slip or expansion joint connection between said header and the boiler.

12. In a steam-generating device, a back connection adapted to be connected to a boiler, a rear header back of said back connection, a series of circulating-pipes divided into two groups, one group being rigidly connected to said header near each end thereof, a front header in front of said back connection, a'second series of circulating-pipes situated between the two groups of the first series and rigidly connected to the front header, and a slip or expansion joint connection between each header and the back connection.

13. In a steam-generating device, a muddrum adapted to be connected directly to a boiler, a rear header back of said mud-drum, circulating-pipes connected to each end of said header, a front headerin front of said mud-drum and between the circulating-pipes connected with the rear header, and a plurality of circulating-pipes connected to the front header, whereby the entire space above the combustion-chamber is utilized.

1%. In a steam-generating device, a muddrum adapted to be rigidly connected directly to a horizontal boiler, a rear header back of said mud-drum, circulating-pipes rigidly connected to each end thereof, a front header in front of said mud-drum, and a plurality of circulating-pipes rigidly connected to said front header and situated between the pipes connected to the back header, said circulating-pipes and headers forming a rigid structure, and a slip or expansion joint connection between said headers and the top of the mud-drum.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HENRY P. J. EARNSI'IAW.

Witnesses:

Louis 0. SMITH, GEO. W. GREGORY. 

